Add constructor calls to RemoveMethodInvocations

[davidh44]

Recipe RemoveMethodInvocations currently does not cover constructor calls. This PR adds functionality for that

What's your motivation?

Would like to remove certain POJO instantiations.

Have you considered any alternatives or workarounds?

As a workaround for my use case, I used a JavaVisitor, checked the JavaType, and returned null.

[timtebeek]

Thanks for the runnable example! Had a brief look. We'll likely need to add something like

    @Override
    public J visitNewClass(J.NewClass newClass, ExecutionContext ctx) {
        J nc = super.visitNewClass(newClass, ctx);
        
        // TODO
        
        return nc;
    }

And then do something very similar to

rewrite/rewrite-java/src/main/java/org/openrewrite/java/RemoveMethodInvocationsVisitor.java

Lines 52 to 72 in d21bb41

	@Override
	public J visitMethodInvocation(J.MethodInvocation method, ExecutionContext ctx) {
	J.MethodInvocation m = (J.MethodInvocation) super.visitMethodInvocation(method, ctx);
	if (inMethodCallChain()) {
	List<Expression> newArgs = ListUtils.map(m.getArguments(), arg -> (Expression) this.visit(arg, ctx));
	return m.withArguments(newArgs);
	}
	J j = removeMethods(m, 0, isLambdaBody(), new Stack<>());
	if (j != null) {
	j = j.withPrefix(m.getPrefix());
	// There should always be
	if (!m.getArguments().isEmpty() && m.getArguments().stream().allMatch(ToBeRemoved::hasMarker)) {
	return ToBeRemoved.withMarker(j);
	}
	}
	//noinspection DataFlowIssue allow returning null to remove the element
	return j;
	}

Where we need a bit more care is to adapt

rewrite/rewrite-java/src/main/java/org/openrewrite/java/RemoveMethodInvocationsVisitor.java

Lines 74 to 77 in d21bb41

	private @Nullable J removeMethods(@Nullable Expression expression, int depth, boolean isLambdaBody, Stack<Space> selectAfter) {
	if (!(expression instanceof J.MethodInvocation) || ((J.MethodInvocation) expression).getMethodType() == null) {
	return expression;
	}

As right now we'd fail on that first conditional; we need to also allow where expression instanceof J.NewClass.

[davidh44]

Added logic for constructor removal and additional tests.

Two issues came up, wondering if you could provide some pointers:

a)
Given that almost all constructor calls will be assigned to a variable, how can we remove the entire line? Should we use visitVariableDeclaration()? Can we view the assignment method there?

b)
As above, we want to remove the entire line, including chained method calls, e.g., new Date().toInstant(). What's the proper way to get rid of the chained method calls?